Jason Castro’s meniscus in his right knee was more damaged than surgeons expected, and the repair was more extensive than planned. As a result, the Twins catcher will miss the rest of the season, the Twins announced Wednesday.

Castro, undergoing surgery at the Steadman Clinic in Vail, Colo., expected to have a small part of the meniscus removed in order to relieve the nagging pain that had bothered him for the past few weeks. But “things did not go as well as hoped,” Twins manager Paul Molitor said. “The [magnetic resonance imaging] didn’t give us a clear picture of what was going on in there. The tear was a little bit more significant. … They had to go ahead and fully repair that meniscus, to try to keep what he had left.”

Castro, 30, who underwent a full medial collateral ligament repair on the same knee in 2011, had been briefed on the possibility by his surgeon, knee specialist Dr. Robert F. LaPrade, and “[Castro] was on board,” Molitor said. “He wanted to protect his future.”

That future involves several weeks of recovery, then several months of rehabilitation before he can return to the baseball field. But doing a full repair should put an end to the occasional flare-ups that have hampered him for the past few seasons. The Twins are optimistic Castro will be ready to play at the start of 2019, the final season on the three-year, $24.5 million contract he signed during the winter of 2016.

“We’re really looking at about a five-to-six-month return,” said Derek Falvey, the Twins’ chief baseball officer. “We anticipate him having a relatively normal offseason.”

Castro started 19 of the first 28 games, and was batting .143 with one home run before the pain grew too persistent to tolerate two weeks ago in Chicago. He went on the disabled list, and Bobby Wilson was called up to replace him on the roster, with Mitch Garver assuming the starting role.

“If we stay the same, I think we’ll all be fine,” Molitor said. “It’s going to give these guys an opportunity. It’s one of those hurdles that comes along when you lose a guy you’re counting on.”

It’s an injury that leaves the Twins particularly vulnerable, because they have no catchers with major league experience — and barely any with Class AAA experience — in their system. Falvey said he is already examining options to provide more depth behind Garver and Wilson.

“We feel like we’re protected in a pinch, but we’re going to pursue potential opportunities to upgrade,” Falvey said. “We have been prepping for [acquiring] depth, and we are now expanding that search, knowing we’re going to have the chance to have somebody impact us for the full season.”

Falvey said the division of playing time is up to Molitor, but he and the manager spoke glowingly of the 35-year-old Wilson’s leadership abilities.

“It’s one of the reasons we recruited him here — his leadership of [the pitching] staff and game-calling and framing,” Falvey said. “So we feel that will be in a good spot.”

Garver is hitting .254 with two home runs, and he had some big hits on the recent 10-game road trip. Wilson, who has played for six different franchises, is 2-for-15 (.133) since being called up, but hit an important two-run home run in the Twins’ 4-1 victory Tuesday.

Castro was “disappointed” when he spoke to Falvey on Tuesday night, but agreed that the injury was clearly hampering him, so a more permanent fix was probably best.

“This [injury probably] impacted him more offensively than it even did defensively. Getting through catching and squatting is not easy, and he would be the last person to complain about it,” Falvey said. “But turning and twisting [while batting], on a meniscus issue, may have led to some of the challenges he had offensively. So I think this will set him up well for the future.”

Garver immediately gave the Twins concern during Wednesday’s game when he was struck on the neck by a foul ball, then on the side of the mask by two more.

“I took a few good shots,” said Garver, who was checked for concussion symptoms every inning after the blows. “I didn’t need to come out of the game, but it definitely hurt.”